Patent GB-447751-A (GB)
Title: Process of and apparatus for removing metal from the surfaces of metallic bodies
IPC: A24F27/10
Filed: 1934-10-22
Abstract: 447,751. Cutting by fusion. LINDE AIR PRODUCTS CO., 30, East 42nd Street, New York, U.S.A. Oct. 22, 1934, No. 30286. Convention date, Oct. 28, 1933. [Class 83 (iv)] Metal is removed from the surface of a ferrous body such as a billet, bar, or slab by an apparatus comprising a number of blowpipes at an acute angle to the surface arranged so that the reaction zones of the individual gas streams merge, the blowpipes being adjustably supported and relative motion being effected between the blowpipes and the body. The blowpipes may have enlarged central passages so that the operation is effected by a large volume of oxidizing gas at relatively low velocity, which removes the metal, preferably partly as oxide and partly in molten state so as to reduce consumption of oxidizing gas. The velocity may vary between 200 and 1000ft. per second, preferably from 550-750 ft. per sec. The metal may be heated by the outer jets of the blowpipes or may be preliminarily heated in a furnace or soaking pit or by a heating flame. The blowpipes 13 for acting on the surface of a steel slab 11, may be secured by screws 24 to a cross-bar 25 fixed to an inclined arm 26, which is mounted on an angularly adjustable bracket 27 on a member 31 ; the member 31 is connected by parallel motion mechanism to a member 39 vertically adjustable in a transversely adjustable slide 45, which is mounted on a longitudinally traversed carriage 44. To adjust the inclination of the nozzles, the bracket 27 is mounted on a pivot 29 on the member 31 and is provided with a pointer 32 moving over a scale 33. The angle of inclination may vary from 10 to 35‹, the angle being increased in order to widen the cut. The parallel motion mechanism which is provided so that the nozzles may ride in contact with the work, consists of the vertical arm 37 of the member 31, which is connected to the arm 38 of the member 39 by links 36, 40, the link 36 being extended and provided with an adjustable counterbalancing weight 35. In order to operate with the nozzles out of contact with the work, the member 39 is adjustable by a rack 49 and pinion 50 in a block 48 carried by the slide 45, the link 36 in this case resting on a stop 43 on the arm 38. The carriage 44 is traversed on a rail 55 supported by brackets 56 on standards 57, by a lead screw 58 engaging a releasable nut 60. The screw is rotated by an electric motor through change speed gear. Cold metal may be cut by moving the nozzles from 4 to 90 feet per minute. The nozzles may cover the whole or only part of the width of the surface. In starting the operation the heating jet is applied to the initial end of the work before the traversing mechanism is started. In an apparatus for simultaneously removing surface metal from all sides of a billet &c., the billet is traversed by a motor M<1> on rollers 112 through a frame provided with four gangs of blowpipes, the oxidized portion from the sides and bottom falling from the surface by gravity. The outer blowpipes are arranged so that rounded corners are obtained. The upper and lower gangs of blowpipes 120 are secured by bars 123 to the member 137 of a parallel motion mechanism, the horizontal elements of which consist of two pairs of links 130, 131 pivoted to the frame 116. The outer link 130 is extended to form a counterbalancing lever 129 so that the nozzles lightly engage the work. The side gangs of blowpipes are secured by bars 1231 to similar parallel motion mechanisms 145, 140, 141, the outer links 140 being formed as bell cranks, the limbs 146 of which are engaged by projections 150 on the counterweighted levers 147. In order that the nozzles may be held out of contact with the work the links 130 and outer links 140 may respectively be formed with further arms 157, 162 connected by links 155, 160 to pistons 151 operated by compressed-air. The angle of the blowpipes may be varied and indicating means provided. In acting on circular bodies the nozzles may be arranged on a circular head surrounding the body with the nozzles converging on the axis thereof. The Specification as open to inspection. under Sect. 91 describes also an apparatus in which the blowpipes are mounted so that they may be rendered operative in either direction of traverse, or may be positioned obliquely to the direction of traverse. This description forms the subject-matter of Specification 447,975 and does not appear in. the present Specification as accepted.